This invention relates to a door construction of a type for mounting on a building which can be opened by hydraulic action.
Doors are opened by hydraulic action are known and various designs have previously been proposed. One problem which arises however is that the force from the hydraulic ram is often communicated to the building structure thus requiring the building structure to be sufficiently strengthened at this point to accommodate the forces involved which can be relatively large when the door opening is large. Other problems which can arise are that the door can often restrict the height of the opening so that it is difficult to access the door opening with larger equipment and that the hydraulic mechanism is often positioned inside the building thus taking up valuable space.
It is one object of the present invention, therefore, to provide an improved design of hydraulically openable door which overcomes or at least reduces some or all of the above problems.
According to the first aspect of the invention there is provided a door arrangement for a building comprising a door, a door frame including a pair of vertical door posts, means mounting the door on the door frame for pivotal movement about a horizontal axis adjacent top of the posts from a closed position in which a plane of the door lies in the same plane as the posts to an open position in which the door extends outwardly from the horizontal axis, first and second coupling means each mounted on the door at a respective side thereof at a position projecting outwardly from the plane of the door, and first and second hydraulic ram means each extending from a base of a respective one of the posts to a respective one of the coupling means, the ram means being extendable from a first position in which the door is closed to a second position raising the door to the open position.
According to the second aspect of the invention there is provided a door arrangement for a building comprising a door, a door frame including a pair of vertical door posts, means mounting the door on the frame for pivotal movement about a horizontal axis adjacent top of the posts from a closed position in which the plane of the door lies in the same plane as the posts to an open position in which the door extends outwardly from the horizontal axis, the door being formed in two parts, a first one of the parts being mounted on the door frame at said horizontal axis for pivotal movement about said horizontal axis and a second of the parts being mounted on the first part and foldable relative thereto about a second axis parallel to said horizontal axis the second part in the open position of the door being arranged such that it is folded under the first part so as to lie directly parallel thereto, and a first and a second lever mechanism extending between said first part of the door and the second part of the door and arranged to cause movement of the second part of the door into the folded position in dependence upon pivotal movement of said first part about said horizontal axis.
The design of door described herein can provide the following advantages:
1. The door can used on implement sheds, workshops, barns, cattle sheds or almost any building requiring a large door.
2. It can be made to very large sizes depending upon the material used for its construction. It can be insulated to the same R-factor as the walls of the building on which it is installed.
3. The door can provide an almost unobstructed ceiling height with no mechanism inside the building.
4. Most of the forces of raising and lowering and folding the door are transferred to the ground level at the base of the posts thus requiring very little extra strength to be built into the building to accommodate the door.
With the foregoing in view, and other advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, the invention is herein described by reference to the accompanying drawings forming a part hereof, which includes a description of the best mode known to the application and of the preferred typical embodiment of the principles of the present invention, in which: